Liane Moriarty had her first story published when she was ten years old. Her mother still thinks it's the best thing she's ever written. Since then she's written seven novels for adults set in the real world, and three books for children set in outer space. Some of her books have been number one best sellers and one has even been made into a TV series. Nicola Berry and The Petrifying Problem with Princess Petronella, the first book in her children's series, was first published in 2007.